Conventional methods for protecting surfaces of top coatings formed as finish coatings on the surfaces of vehicles include coating thinly with paraffin wax. However, this method involves a problem in that the paraffin wax coating does not exhibit sufficient protecting function and that it costs much time and labor when the paraffin wax coating is to be removed.
Meanwhile, Japanese Patent Publication No. 74627/1993 discloses a method of applying a plastic film having a pressure-sensitive adhesive layer to an adherend. According to this method, the above problems can be solved. In this case, however, the pressure-sensitive adhesive layer is based on a hydrogenated block copolymer of styrene and a diene type hydrocarbon, so that the pressure-sensitive adhesive layer exhibits poor adhesion and poor removability against adherends and that the pressure-sensitive adhesive layer leaves stains of the adherends or leaves thereon traces of the films removed, disadvantageously.
The purpose of the present invention is to provide a pressure-sensitive adhesive composition for surface-protective films which is caused to exhibit excellent adhesion to adherends, not to smear the adherends nor to leave traces thereon when the films are removed from the adherends and can also impart excellent removability to surf ace-protective films.